Pbotectoe



F. SMARCH. PROTECTOR FOR TROMMEL SPOKES.

APPLICATION FILED MAR. 31, 1920.

l, 35 1 699. I Patented Aug. 31, 1920.,

'INvEN-roR ATTO R N EY ATE FRANK SIVIABCH, or ANAGONDA, MONTANA.

PROTECTOR FOR TROMMEL-SPOKES.

Application filed March 31, 1920. Serial No. 370,314.

To all whom it may concern:

Be it known that I, FRANK SMARoH, a citizen of the United States, residing at Anaconda, in the county of Deerlodge and State of Montana, have invented a new and useful Protector for Trommel-Spokes, of which the following is a specification.

This invention has reference to protectors for trommel spokes and its object is to protect trommel spokes against wear from material directed into the trommel; ,or to protect the spokes, after having become worn, from further wear and thus avoiding the necessity of replacing the spokes.

Customarily a trommel is of considerable length and is provided with a number of sets of radial spokes, usually three or four sets, with the sets arranged lengthwise of the trommel and the spokes of each set radiating from a central hub mounted on a shaft sustaining the trommel and about the longitudinal axis of which the trommel is rotated. It is the center of the spokes at the entering end of the trommel which are particularly liable to damage by the entering material, which material is more or less abrasive. For this reason the first 'set of spokes in order of travel of the material through the trommel becomes worn with considerable rapidity so that the life of such spokes is relatively short, since the wear, suflicient to demand a renewal of the spokes, is rapid enough to make the renewal of the spokes represent a material part of the cost of maintenance.

Experience has shown that, not'only the bodies of the spokes soon wear to a dangerone degree, but such wear also occurs where the outerends of the spokes are connected to the rim portion of the trommel where the wear may ultimately loosen the usual connecting bolts sufiiciently to permit them to drop out.

The invention provides a shield or protector, partially or completely surrounding the spokes where liable to wear, and housing the outer head ends of the spokes and the bolts or rivets holding the spokes in place. Y j

The invention is an improvement upon the trommel spoke protector shown and described in Letters Patent No. 1,319,309, granted to me October 21, 1919. In said Letters Patent the protector is constructed and located to shield a portion of the spoke about midway of the length thereof. In

accordance with this invention the shield not only protects the spoke in the location corresponding to that provided for in the Letters Patent, but is made to house the outer end of the spoke where it is formed into a head constituting the attaching head for the outer end of the spoke, with the shield also protecting the bolts or rivets constituting the attaching means for the head of the spoke. I

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding however, that the invention is not confined to any strict conformity with the showing in the drawing, but may be changed and modified so long as such changes and modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing,

Figure l is an elevation of a trommel spoke attached to the hub and rim portions of the trommel and provided with a protector.

Fig. 2 is'a view similar to Fig. 1, but showing a portion of the shield removed.

Fig. 8 is an elevation of a trommel spoke with a shield applied and viewed at a point at right angles to the showing of Fig. 1.

Fig. 4; is a section on the line 4-4 of Big. 3.

Referring to the drawing, there is shown a portion of a trommel 1, which may be considered as of ordinary construction and, therefore, requiring no particular or ex tended description or showing.

The trommel is provided with a shaft 2 upon which the hubs 3 are mounted, only 7 one such hub being indicated in the drawing, but it is to be understood that each has as many hubs as are needed. The hubs each carry a set of spokes 4 and, as the spokes are all alike,'but one spoke is shown in the drawing for the sake of simplicity of illustration. Spoke 4 has a threaded end 5 ar ranged to be screwed into the hub 3 and there held by a locknut 6. The other or outer end of each spoke terminates ina head 7 which, in a new spoke is symmetrical, but, in the showing of the drawing the head of the spoke and the adjacent portion of the stem of the spoke, are assumed to have been worn away more or less, as shown at 8, by the abrasion of incoming material.

Such wear rapidly shortens the life of the trommel because it results in reducing the thickness of the spoke and the amount 5f material in the head end 7 of the spoke so that, unless prevented, the spoke ultimately becomes so thin as to break under ordinary working conditions; or the rivets 9, or other fastening devices whereby the head 7 of the spoke is joined to the rim 1, become loosened and fall out, demanding repairs and renewals resulting in loss of time and considerable expense from other causes.

In order to restore the working condition of the spoke, or to protect the spoke from wear so that there is no diminution of the strength of the trommel even after extended use, the invention contemplates the provision of a shield 10 which may be made up of two half sleeves, 13 and 14, shaped so as, when placed together in embracing relation to the spoke 4 the latter is practically surrounded by the shield with such shield extending from and protecting the head 7 of the spoke to, substantially, the screw threaded end 5 of the spoke. The shield members have expanded ends 15 shaped to overlie the heads 7 and provided with sockets 16 to receive the heads of the rivets 9. The sleeve 10, with its laterally expanded portion, is made sufficiently thick to provide an extended life. The two members, 18 and 1 1, of the protecting sleeve end are provided with matching ears 17, perforated for the passage of bolts 18, or any other suitable means, for the purpose of holding the sleeve members tightly in'position about the spoke with the laterally expanded, or headed, portion 15 in protecting relation to the head 7 of the spoke, and the shank of the sleeve 10 in surrounding relation to the shank of the spoke; wherefore the material, fed into the trommel from a chute like that shown in the aforesaid Letters Patent, will not strike the spokes but will strike the sleeves 10, and wear, which would otherwise occur on the spokes, is taken up by the sleeve, thus protecting the spokes either from initial wear or further wear in case the protecting sleeves are applied to trommels after they have already been subjected to some wear. In the last named case the protecting sleeves are useful as protecting means for trommels which have already been in use for some time without the protecting sleeves, thus avoiding further wear and prolonging the life of the trommel indefinitely, especially where the wear of the spokes has been insufficient to materially weaken the spokes.

The invention is particularly useful in trommels where the wear by the incoming material is such as to affect the heads of the spokes and the rivets holding them to the rim of the trommel; and a protector such as is shown in the aforesaid Letters Patent would be insufficient to avoid ultimate loosening of the spokes where the trommel is so constructed that the incoming material may reach the heads of the spokes where connected to the rim and, consequently, would not fully protect the spokes and replacements would be needed (possibly not as frequently as when the shield does not protect the heads of the spokes).

The ears 17 are so located as to be out'of the path of the incoming material and hence the bolts, or other clamping devices 18, are not subjected to wear so that renewals of these parts are unnecessary. The shield is held sufiiciently tight by the bolts 18, since the abutment of the head end 15 of the shield against the rim 1 prevents any longitudinal movement of the shield during the operation of the trommel.

The thickness of the shield may be as great as, or greater than, the spoke; and one member of the shield may be thicker than the other, as in the aforesaid Letters Patent.

What is claimed is: i

1: In a trommel wherein are employed radial spokes each with an expanded head for abutment against the rim of the trommel, means for protecting the stems of the spokes and the heads of the spokes from wear, consisting of a longitudinal divided sleeve adapted to be applied about the spoke and fastened thereto, said sleeve having a laterally expanded end portion adapted to over-ride and house the head end of the spoke and press against the inner periphery of the rim and the fastening means whereby the head end of the spoke is made fast to the rim of the trommel.

2. In a trommel provided with a series of radial spokes each having an expanded head for securing the spoke to the rim of the trommel, means for protecting both the spoke and the expanded head from the wearing effect of material entering the trommel consisting of a divided sleeve. for embracing the spoke, and having a similarly divided head expanded in the direction of the length of the head of the spoke and having cavities for together receiving the head of the spoke and the fastening means'securing the spoke to the rim of the trommel, whereby the spoke and the head of the spoke are housed in the protecting means.

In testimony, that I claim the foregoing as my own, I have hereto affixed my signature.

FRANK SMARCH. 

